1. Field of the Invention
The invention relates to the field of hearing aids. The invention, more specifically, relates to hearing aids having an input transducer, a signal processing unit, a power supply unit, and an output transducer. The invention particularly relates to the field of remote controls for hearing aids. The invention further relates to a method of controlling the state of a hearing aid.
Within the context of the present disclosure, a hearing aid should be understood as a small, battery-powered, microelectronic device designed to be worn behind or in the human ear by a hearing-impaired user. A hearing aid comprises one or more microphones, a battery, a microelectronic circuit comprising a signal processor, and an acoustic output transducer. The signal processor is preferably a digital signal processor. The hearing aid is enclosed in a casing suitable for fitting behind or in a human ear. The hearing aid serves to alleviate a hearing loss by amplifying sound at frequencies in those parts of the audible frequency range where the user suffers a hearing deficit.
2. The Prior Art
EP-A2-2043388 discloses a hearing aid system of two hearing aids connected with each other through a wireless connection. As the distance between the two hearing aids is constant while in operation at the respective ears of the user, the signal strength of the wireless connection will be constant. If the hearing aids are removed from the users' ears and placed in a box, the signal strength will increase due to the decrease in distance between the two hearing aids. The hearing aids will power-off, when the signal strength reaches a threshold limit.
DE-C2-3109049 discloses a hearing aid with magnetic switches for changing the state of a hearing aid by a magnetic field. Thus, by displacement of a magnet, the state of the hearing aid can be changed.
EP-A2-2028881 discloses two hearing aids capable of communicating with each other through a wireless link and having a mechanism monitoring the signal strength of the magnetic field. If the signal strength increases in only one hearing aid, it can be inferred, that it is a “telephoning” situation, and the program will change accordingly. If the magnetic field increases in both hearing aids, it is inferred that the two hearing aids are in very close proximity of each other and they will power of.
US-A1-20080123882 discloses a hearing aid having means for detecting a change in an acoustic path, whereby it is established that the hearing aid is no longer placed in the ear of the user, accordingly the hearing aid at least partially powers off.
U.S. Pat. No. 5,202,927 provides a remote-controllable, programmable hearing aid system, including a hearing aid with incorporated amplifier and with a signal processing circuit whose transmission characteristic can be determined at any time by a set of control parameters, and an external control unit with a transmitter for wireless transmission of control parameters to the hearing aid. A receiving circuit for receiving the control parameters is located in the hearing aid.
WO-A1-2009076949 provides a hearing aid having means for entering or leaving a stand-by mode initiated by a remote control. During use, a dedicated stand-by command issued by the remote control is received and decoded in the hearing aid.
Many hearing aids today can be controlled by a remote control, which gives the user of the hearing aid an easier way to control the hearing aid. In some cases the user might also be able to power-off the hearing aid or change the state to a stand-by mode using the remote control, where the hearing aid turns off most processing, keeping power on at just a minimum of circuits sufficient to power up the hearing aid from the stand-by mode using the remote control.
For a lot of elderly people with a hearing loss the handling of hearing aids can be difficult, because they are small, so that it is not easy to manipulate control buttons or to visually recognize whether the hearing aids are turned on or off. Consequently a lot of elderly people do not turn off their hearing aids when they are not in use, which drains the batteries quickly and decreases the life time of the batteries.